Pfaff Creative 1467 Presser foot does not go down with using the up/down lever. Can push it down and the lever can lift it back up, but it may be gunked up and stuck in the up position. How to fix?

SOURCE: Model 6230- presser foot lifter won't move presser foot

That's the problem seized up use a penetrating oil from the top and work it up and down and it should free up

SOURCE: Pfaff Creative 1371

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SOURCE: pfaff 2144 presser foot lift

sounds like something has come loose or is broken, the machine needs to be serviced

SOURCE: I have a pfaff hobbylock 796.

Has any little kids been around lately? Have they had access to your sewing area and machine? (thinking perhaps the pressure foot tension has been tightened down) If it has been tightened, losen it a couple turns, see if that helps (remember, left to loosen, right to tighten)

When is the last time you oiled this machine? Typically sergers require a clean and oil each time you go to use them. Locate the bar that correlates to the presser foot add a drop of oil to the bar and let it seep in. After a few minutes try lifting the presser foot.

Also does the presser foot lever move at all?

SOURCE: The presser foot on my Janome MC9000 will not go up or down

yeah the cam lever is probably broken. Time for a new machine???